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Autonomous Vehicle Platoons In Urban Road Networks:A Joint Distributed Reinforcement Learning and Model Predictive Control Approach
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作者 Luigi D’Alfonso Francesco Giannini +3 位作者 Giuseppe Franzè Giuseppe Fedele Francesco Pupo Giancarlo Fortino 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期141-156,共16页
In this paper, platoons of autonomous vehicles operating in urban road networks are considered. From a methodological point of view, the problem of interest consists of formally characterizing vehicle state trajectory... In this paper, platoons of autonomous vehicles operating in urban road networks are considered. From a methodological point of view, the problem of interest consists of formally characterizing vehicle state trajectory tubes by means of routing decisions complying with traffic congestion criteria. To this end, a novel distributed control architecture is conceived by taking advantage of two methodologies: deep reinforcement learning and model predictive control. On one hand, the routing decisions are obtained by using a distributed reinforcement learning algorithm that exploits available traffic data at each road junction. On the other hand, a bank of model predictive controllers is in charge of computing the more adequate control action for each involved vehicle. Such tasks are here combined into a single framework:the deep reinforcement learning output(action) is translated into a set-point to be tracked by the model predictive controller;conversely, the current vehicle position, resulting from the application of the control move, is exploited by the deep reinforcement learning unit for improving its reliability. The main novelty of the proposed solution lies in its hybrid nature: on one hand it fully exploits deep reinforcement learning capabilities for decisionmaking purposes;on the other hand, time-varying hard constraints are always satisfied during the dynamical platoon evolution imposed by the computed routing decisions. To efficiently evaluate the performance of the proposed control architecture, a co-design procedure, involving the SUMO and MATLAB platforms, is implemented so that complex operating environments can be used, and the information coming from road maps(links,junctions, obstacles, semaphores, etc.) and vehicle state trajectories can be shared and exchanged. Finally by considering as operating scenario a real entire city block and a platoon of eleven vehicles described by double-integrator models, several simulations have been performed with the aim to put in light the main f eatures of the proposed approach. Moreover, it is important to underline that in different operating scenarios the proposed reinforcement learning scheme is capable of significantly reducing traffic congestion phenomena when compared with well-reputed competitors. 展开更多
关键词 distributed model predictive control distributed reinforcement learning routing decisions urban road networks
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Observer-based dynamic event-triggered control for distributed parameter systems over mobile sensor-plus-actuator networks
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作者 穆文英 庄波 邱芳 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期237-243,共7页
We develop a policy of observer-based dynamic event-triggered state feedback control for distributed parameter systems over a mobile sensor-plus-actuator network.It is assumed that the mobile sensing devices that prov... We develop a policy of observer-based dynamic event-triggered state feedback control for distributed parameter systems over a mobile sensor-plus-actuator network.It is assumed that the mobile sensing devices that provide spatially averaged state measurements can be used to improve state estimation in the network.For the purpose of decreasing the update frequency of controller and unnecessary sampled data transmission, an efficient dynamic event-triggered control policy is constructed.In an event-triggered system, when an error signal exceeds a specified time-varying threshold, it indicates the occurrence of a typical event.The global asymptotic stability of the event-triggered closed-loop system and the boundedness of the minimum inter-event time can be guaranteed.Based on the linear quadratic optimal regulator, the actuator selects the optimal displacement only when an event occurs.A simulation example is finally used to verify that the effectiveness of such a control strategy can enhance the system performance. 展开更多
关键词 distributed parameter systems event-triggered control mobile sensors mobile actuators
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Superior Mechanical Behavior and Flame Retardancy FRP via a Distribution Controllable 1D/2D Hybrid Nanoclay Synergistic Toughening Strategy
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作者 Zixuan Chen Tianyu Yu +4 位作者 Zetian Yang Zhibiao Wei Yan Li Weidong Yang Tao Yu 《Engineering》 SCIE EI CAS CSCD 2024年第9期166-178,共13页
The incorporation of commercial flame retardants into fiber-reinforced polymer(FRP)composites has been proposed as a potential solution to improve the latter’s poor flame resistance.However,this approach often poses ... The incorporation of commercial flame retardants into fiber-reinforced polymer(FRP)composites has been proposed as a potential solution to improve the latter’s poor flame resistance.However,this approach often poses a challenge,as it can adversely affect the mechanical properties of the FRP.Thus,balancing the need for improved flame resistance with the preservation of mechanical integrity remains a complex issue in FRP research.Addressing this critical concern,this study introduces a novel additive system featuring a combination of one-dimensional(1D)hollow tubular structured halloysite nanotubes(HNTs)and two-dimensional(2D)polygonal flake-shaped nano kaolinite(NKN).By employing a 1D/2D hybrid kaolinite nanoclay system,this research aims to simultaneously improve the flame retardancy and mechanical properties.This innovative approach offers several advantages.During combustion and pyrolysis processes,the 1D/2D hybrid kaolinite nanoclay system proves effective in reducing heat release and volatile leaching.Furthermore,the system facilitates the formation of reinforcing skeletons through a crosslinking mechanism during pyrolysis,resulting in the development of a compact char layer.This char layer acts as a protective barrier,enhancing the material’s resistance to heat and flames.In terms of mechanical properties,the multilayered polygonal flake-shaped 2D NKN plays a crucial role by impeding the formation of cracks that typically arise from vulnerable areas,such as adhesive phase particles.Simultaneously,the 1D HNT bridges these cracks within the matrix,ensuring the structural integrity of the composite material.In an optimal scenario,the homogeneously distributed 1D/2D hybrid kaolinite nanoclays exhibit remarkable results,with a 51.0%improvement in mode II fracture toughness(GIIC),indicating increased resistance to crack propagation.In addition,there is a 34.5%reduction in total heat release,signifying improved flame retardancy.This study represents a significant step forward in the field of composite materials.The innovative use of hybrid low-dimensional nanomaterials offers a promising avenue for the development of multifunctional composites.By carefully designing and incorporating these nanoclays,researchers can potentially create a new generation of FRP composites that excel in both flame resistance and mechanical strength. 展开更多
关键词 1D/2D nanoclays Hierarchical distribution Flame retardancy Fiber-reinforced polymer Damage mechanism
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Virtually coupled train set control subject to space-time separation:A distributed economic MPC approach with emergency braking configuration
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作者 Xiaolin Luo Tao Tang +1 位作者 Le Wang Hongjie Liu 《High-Speed Railway》 2024年第3期143-152,共10页
The emerging virtual coupling technology aims to operate multiple train units in a Virtually Coupled Train Set(VCTS)at a minimal but safe distance.To guarantee collision avoidance,the safety distance should be calcula... The emerging virtual coupling technology aims to operate multiple train units in a Virtually Coupled Train Set(VCTS)at a minimal but safe distance.To guarantee collision avoidance,the safety distance should be calculated using the state-of-the-art space-time separation principle that separates the Emergency Braking(EB)trajectories of two successive units during the whole EB process.In this case,the minimal safety distance is usually numerically calculated without an analytic formulation.Thus,the constrained VCTS control problem is hard to address with space-time separation,which is still a gap in the existing literature.To solve this problem,we propose a Distributed Economic Model Predictive Control(DEMPC)approach with computation efficiency and theoretical guarantee.Specifically,to alleviate the computation burden,we transform implicit safety constraints into explicitly linear ones,such that the optimal control problem in DEMPC is a quadratic programming problem that can be solved efficiently.For theoretical analysis,sufficient conditions are derived to guarantee the recursive feasibility and stability of DEMPC,employing compatibility constraints,tube techniques and terminal ingredient tuning.Moreover,we extend our approach with globally optimal and distributed online EB configuration methods to shorten the minimal distance among VCTS.Finally,experimental results demonstrate the performance and advantages of the proposed approaches. 展开更多
关键词 Virtually coupled train set Space-time separation Economic model predictive control distributed model predictive control Emergency braking configuration
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Glucagon-like peptide-1 receptor agonists:Exploring the mechanisms from glycemic control to treatment of multisystemic diseases
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作者 Mo-Wei Kong Yang Yu +2 位作者 Ying Wan Yu Gao Chun-Xiang Zhang 《World Journal of Gastroenterology》 SCIE CAS 2024年第36期4036-4043,共8页
This editorial takes a deeper look at the insights provided by Soresi and Giannitrapani,which examined the therapeutic potential of glucagon-like peptide-1 receptor agonists(GLP-1RAs)for metabolic dysfunction-associat... This editorial takes a deeper look at the insights provided by Soresi and Giannitrapani,which examined the therapeutic potential of glucagon-like peptide-1 receptor agonists(GLP-1RAs)for metabolic dysfunction-associated fatty liver disease.We provide supplementary insights to their research,highlighting the broader systemic implications of GLP-1RAs,synthesizing the current understanding of their mechanisms and the trajectory of research in this field.GLP-1RAs are revolutionizing the treatment of type 2 diabetes mellitus and beyond.Beyond glycemic control,GLP-1RAs demonstrate cardiovascular and renal protective effects,offering potential in managing diabetic kidney disease alongside renin–angiotensin–aldosterone system inhibitors.Their role in bone metabolism hints at benefits for diabetic osteoporosis,while the neuroprotective properties of GLP-1RAs show promise in Alzheimer's disease treatment by modulating neuronal insulin signaling.Additionally,they improve hormonal and metabolic profiles in polycystic ovary syndrome.This editorial highlights the multifaceted mechanisms of GLP-1RAs,emphasizing the need for ongoing research to fully realize their therapeutic potential across a range of multisystemic diseases. 展开更多
关键词 Glucagon-like peptide-1 receptor agonists Glycemic control Multisystem diseases Mechanism of action Cardiovascular protection Renal disease Bone metabolism Non-alcoholic fatty liver disease NEUROPROTECTION Polycystic ovary syndrome
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黏蛋白1在甲状腺癌中表达临床意义的Meta分析
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作者 罗锦 李岚 +3 位作者 张睿 马健波 方静怡 朱正鹏 《检验医学与临床》 CAS 2024年第22期3331-3336,3341,共7页
目的通过Meta分析探讨甲状腺癌组织中黏蛋白1(MUC1)表达的临床意义及其与各临床病理参数的相关性。方法检索维普、万方、中国知网、中国生物医学文献、PubMed、Web of Science、Embase、Cochrane中英文数据库中关于MUC1在甲状腺癌中表... 目的通过Meta分析探讨甲状腺癌组织中黏蛋白1(MUC1)表达的临床意义及其与各临床病理参数的相关性。方法检索维普、万方、中国知网、中国生物医学文献、PubMed、Web of Science、Embase、Cochrane中英文数据库中关于MUC1在甲状腺癌中表达及其意义的文献,以比值比(OR)和95%置信区间(95%CI)为效应指标,采用STATA 14软件进行Meta分析,并对发表偏倚及敏感性进行检验。结果共纳入13项病例对照研究,甲状腺癌病例组共1157例,非甲状腺癌对照组共509例。结果显示,甲状腺癌病例组MUC1表达明显高于非甲状腺癌对照组(OR=9.78,95%CI:7.49~12.78,P<0.001);伴有淋巴结转移的甲状腺癌组织中MUC1表达高于无淋巴结转移的甲状腺癌组织(OR=3.08,95%CI:1.37~6.92,P<0.05);TNM分期为Ⅲ~Ⅳ期的甲状腺癌组织中MUC1表达高于TNM分期为Ⅰ~Ⅱ期的甲状腺癌组织(OR=1.88,95%CI:1.22~2.90,P<0.05)。结论与非甲状腺癌对照组比较,甲状腺癌病例组MUC1呈高表达,且MUC1高表达与淋巴结转移、TNM分期密切相关。MUC1与甲状腺癌的发生和发展存在相关性,有望成为甲状腺癌分子研究领域的一项新靶标。 展开更多
关键词 甲状腺癌 黏蛋白1 META分析 病例对照 病理参数
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支气管哮喘患儿血清LCN2、SDC⁃1水平及临床意义
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作者 杨颖 刘亚昆 董天津 《广西医学》 CAS 2024年第5期653-656,共4页
目的分析支气管哮喘患儿血清脂质运载蛋白2(LCN2)和多配体蛋白聚糖1(SDC⁃1)水平,并探讨两者与病情严重程度、哮喘控制水平的关系,以及对儿童支气管哮喘的诊断价值。方法纳入112例支气管哮喘患儿作为哮喘组,104例健康儿童作为正常组。根... 目的分析支气管哮喘患儿血清脂质运载蛋白2(LCN2)和多配体蛋白聚糖1(SDC⁃1)水平,并探讨两者与病情严重程度、哮喘控制水平的关系,以及对儿童支气管哮喘的诊断价值。方法纳入112例支气管哮喘患儿作为哮喘组,104例健康儿童作为正常组。根据病情严重程度再将哮喘组患儿分为轻度间歇组(36例)、轻度持续组(25例)、中度持续组(32例)和重度持续组(19例)。比较哮喘组与正常组之间,以及哮喘组不同病情严重程度患儿之间血清LCN2、SDC⁃1水平。分析哮喘组患儿血清LCN2和SDC⁃1的相关性,以及二者与第1秒用力呼气量(FEV_(1))、FEV_(1)/用力肺活量(FVC)值、儿童哮喘控制测试(C⁃ACT)评分的相关性。绘制受试者工作特征(ROC)曲线分析血清LCN2、SDC⁃1水平对儿童支气管哮喘的诊断价值。结果与正常组相比,哮喘组血清LCN2、SDC⁃1水平升高(P<0.05)。轻度间歇组、轻度持续组、中度持续组、重度持续组支气管哮喘患儿血清LCN2、SDC⁃1水平依次升高(P<0.05)。支气管哮喘患儿血清LCN2水平与血清SDC⁃1水平呈正相关,血清LCN2和SDC⁃1水平分别与FEV_(1)、FEV_(1)/FVC值、C⁃ACT评分呈负相关(P<0.05)。血清LCN2、SDC⁃1水平联合诊断儿童支气管哮喘的曲线下面积(AUC)为0.881,大于血清LCN2、SDC⁃1水平单独诊断的AUC(分别为0.778和0.768,P<0.05)。结论支气管哮喘患儿血清LCN2、SDC⁃1水平升高,且与病情严重程度和哮喘控制水平有关。血清LCN2、SDC⁃1水平可作为辅助诊断儿童支气管哮喘的生物标志物,且两者联合诊断的效能更高。 展开更多
关键词 支气管哮喘 脂质运载蛋白2 多配体蛋白聚糖1 病情严重程度 哮喘控制 诊断效能 儿童
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Data-Driven Control of Distributed Event-Triggered Network Systems 被引量:7
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作者 Xin Wang Jian Sun +2 位作者 Gang Wang Frank Allgower Jie Chen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第2期351-364,共14页
The present paper deals with data-driven event-triggered control of a class of unknown discrete-time interconnected systems(a.k.a.network systems).To this end,we start by putting forth a novel distributed event-trigge... The present paper deals with data-driven event-triggered control of a class of unknown discrete-time interconnected systems(a.k.a.network systems).To this end,we start by putting forth a novel distributed event-triggering transmission strategy based on periodic sampling,under which a model-based stability criterion for the closed-loop network system is derived,by leveraging a discrete-time looped-functional approach.Marrying the model-based criterion with a data-driven system representation recently developed in the literature,a purely data-driven stability criterion expressed in the form of linear matrix inequalities(LMIs)is established.Meanwhile,the data-driven stability criterion suggests a means for co-designing the event-triggering coefficient matrix and the feedback control gain matrix using only some offline collected state-input data.Finally,numerical results corroborate the efficacy of the proposed distributed data-driven event-triggered network system(ETS)in cutting off data transmissions and the co-design procedure. 展开更多
关键词 Data-driven control distributed event-triggered network system(ETS) linear matrix inequalitie(LMI) looped-functional STABILITY
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An Optimal Control-Based Distributed Reinforcement Learning Framework for A Class of Non-Convex Objective Functionals of the Multi-Agent Network 被引量:2
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作者 Zhe Chen Ning Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第11期2081-2093,共13页
This paper studies a novel distributed optimization problem that aims to minimize the sum of the non-convex objective functionals of the multi-agent network under privacy protection, which means that the local objecti... This paper studies a novel distributed optimization problem that aims to minimize the sum of the non-convex objective functionals of the multi-agent network under privacy protection, which means that the local objective of each agent is unknown to others. The above problem involves complexity simultaneously in the time and space aspects. Yet existing works about distributed optimization mainly consider privacy protection in the space aspect where the decision variable is a vector with finite dimensions. In contrast, when the time aspect is considered in this paper, the decision variable is a continuous function concerning time. Hence, the minimization of the overall functional belongs to the calculus of variations. Traditional works usually aim to seek the optimal decision function. Due to privacy protection and non-convexity, the Euler-Lagrange equation of the proposed problem is a complicated partial differential equation.Hence, we seek the optimal decision derivative function rather than the decision function. This manner can be regarded as seeking the control input for an optimal control problem, for which we propose a centralized reinforcement learning(RL) framework. In the space aspect, we further present a distributed reinforcement learning framework to deal with the impact of privacy protection. Finally, rigorous theoretical analysis and simulation validate the effectiveness of our framework. 展开更多
关键词 distributed optimization MULTI-AGENT optimal control reinforcement learning(RL)
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Differential flatness-based distributed control of underactuated robot swarms 被引量:1
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作者 Ningbo AN Qishao WANG +1 位作者 Xiaochuan ZHAO Qingyun WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第10期1777-1790,共14页
This paper proposes a distributed control method based on the differential flatness(DF) property of robot swarms. The swarm DF mapping is established for underactuated differentially flat dynamics, according to the co... This paper proposes a distributed control method based on the differential flatness(DF) property of robot swarms. The swarm DF mapping is established for underactuated differentially flat dynamics, according to the control objective. The DF mapping refers to the fact that the system state and input of each robot can be derived algebraically from the flat outputs of the leaders and the cooperative errors and their finite order derivatives. Based on the proposed swarm DF mapping, a distributed controller is designed. The distributed implementation of swarm DF mapping is achieved through observer design. The effectiveness of the proposed method is validated through a numerical simulation of quadrotor swarm synchronization. 展开更多
关键词 differential flatness(DF) underactuated robot distributed control SYNCHRONIZATION
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塔里木盆地顺北1号断裂带奥陶系碳酸盐岩储层结构表征及三维地质建模
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作者 陈叔阳 何云峰 +3 位作者 王立鑫 尚浩杰 杨昕睿 尹艳树 《岩性油气藏》 CAS CSCD 北大核心 2024年第2期124-135,共12页
综合利用地震、测井、岩心以及动态生产资料,对塔里木盆地顺北1号断裂带断控型碳酸盐岩储集体的内部结构进行了层级划分;基于层级划分,通过地震资料属性提取与转换、深度学习、基于目标示性点过程模拟以及离散裂缝网络模拟(DFN)等方法... 综合利用地震、测井、岩心以及动态生产资料,对塔里木盆地顺北1号断裂带断控型碳酸盐岩储集体的内部结构进行了层级划分;基于层级划分,通过地震资料属性提取与转换、深度学习、基于目标示性点过程模拟以及离散裂缝网络模拟(DFN)等方法建立了三维地质模型,并以模型进行油气储量和油藏数值模拟,将拟合结果与实际生产数据进行对比。研究结果表明:(1)顺北1号断裂带奥陶系断控型储层按层级由大到小分为走滑断裂影响带、断控体、类洞穴、类洞穴内簇充填和裂缝带共5个层级。(2)走滑断裂影响带受应力差异影响具有分段性,可细分为挤压段、拉分段和平移段;断控体在拉分段发育断裂交会型、单支走滑型,在平移段发育双断裂交错型和两断裂交会型,在挤压段发育双断裂扭曲型和双断裂交会型,共有6种平面组合样式;类洞穴在地震剖面上呈串珠状反射特征;类洞穴内部分为栅体与栅间(基岩),其中栅体又可进一步分为簇(角砾带)、簇间(裂缝带),整体表现为栅状结构,簇的物性更好;裂缝带为类洞穴的主要储集空间,在簇内部比簇间更发育,在一间房组比鹰山组更发育,一间房组和鹰山组均以发育高角度裂缝为主,在两者连接处则以发育水平缝为主。(3)地质模型预测的油气储量与地质分析储量误差为1.75%,模型模拟的生产井地层压力及累产液结果与生产动态吻合度较高,拟合误差小于10%。 展开更多
关键词 走滑断裂带 断控体 类洞穴 碳酸盐岩储层 三维地质建模 深度学习 奥陶系 顺北1号断裂带 塔里木盆地
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顺北1号走滑断裂带分段差异活动特征及其控藏效应 被引量:1
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作者 古再丽努尔·艾尔肯 曹自成 +4 位作者 耿锋 骆福嵩 唐大卿 伍亮 王玮龙 《断块油气田》 CAS CSCD 北大核心 2024年第4期589-598,共10页
塔里木盆地塔中北坡众多大型走滑断裂带是近年油气勘探开发的重点,文中通过对顺北1号走滑断裂带三维地震资料精细解释,综合前人研究成果及油气勘探实践,探讨了顺北1号走滑断裂带的差异活动特征及其控藏效应。研究表明:1)顺北1号走滑断... 塔里木盆地塔中北坡众多大型走滑断裂带是近年油气勘探开发的重点,文中通过对顺北1号走滑断裂带三维地震资料精细解释,综合前人研究成果及油气勘探实践,探讨了顺北1号走滑断裂带的差异活动特征及其控藏效应。研究表明:1)顺北1号走滑断裂带主要发育于下古生界,为一条大型左行走滑断裂带,平面展布具有分层差异性,在下古生界为线性展布,在上古生界呈雁列式展布。2)顺北1号走滑断裂带分段差异活动特征明显,研究区内可划分出张扭、压扭和纯走滑等3类12段。3)顺北1号走滑断裂带经历了多期构造演化,其中,加里东中期Ⅰ幕、加里东中期Ⅲ幕、加里东晚期—海西早期为顺北1号走滑断裂带的关键活动时期,此后的深埋阶段构造相对稳定,断裂活动微弱。4)顺北1号走滑断裂带沟通了寒武系优质烃源岩与奥陶系有利储集体,断裂带的分段差异活动造成了不同断裂段的断溶体发育程度的差异及油藏规模的差异。实钻数据表明,张扭段和压扭段油气富集程度高,纯走滑段较低。此外,主断裂与分支断裂交叉处通常高产,推测分支断裂规模及活动强弱控制了其油气富集程度。 展开更多
关键词 差异活动 控藏效应 顺北地区 顺北1号走滑断裂带 塔里木盆地
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Operation Control Method of Relay Protection in Flexible DC Distribution Network Compatible with Distributed Power Supply
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作者 Zihan Qi 《Energy Engineering》 EI 2023年第11期2547-2563,共17页
A novel operation control method for relay protection in flexible DC distribution networks with distributed power supply is proposed to address the issue of inaccurate fault location during relay protection,leading to... A novel operation control method for relay protection in flexible DC distribution networks with distributed power supply is proposed to address the issue of inaccurate fault location during relay protection,leading to poor performance.The method combines a fault-tolerant fault location method based on long-term and short-term memory networks to accurately locate the fault section.Then,an operation control method for relay protection based on adaptive weight and whale optimization algorithm(WOA)is used to construct an objective function considering the shortest relay protection action time and the smallest impulse current.The adaptive weight and WOA are employed to obtain the optimal strategy for relay protection operation control,reducing the action time and impulse current.Experimental results demonstrate the effectiveness of the proposed method in accurately locating faults and improving relay protection performance.The longest operation time is reduced by 4.7023 s,and the maximum impulse current is limited to 0.3 A,effectively controlling the impact of large impulse currents and enhancing control efficiency. 展开更多
关键词 Compatible distributed power supply FLEXIBILITY DC distribution network relay protection operation control
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Glucagon-like peptide-1 receptor agonists as a possible intervention to delay the onset of type 1 diabetes:A new horizon 被引量:1
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作者 Mahmoud Nassar Ajay Chaudhuri +1 位作者 Husam Ghanim Paresh Dandona 《World Journal of Diabetes》 SCIE 2024年第2期133-136,共4页
Type 1 diabetes(T1D)is a chronic autoimmune condition that destroys insulinproducing beta cells in the pancreas,leading to insulin deficiency and hyperglycemia.The management of T1D primarily focuses on exogenous insu... Type 1 diabetes(T1D)is a chronic autoimmune condition that destroys insulinproducing beta cells in the pancreas,leading to insulin deficiency and hyperglycemia.The management of T1D primarily focuses on exogenous insulin replacement to control blood glucose levels.However,this approach does not address the underlying autoimmune process or prevent the progressive loss of beta cells.Recent research has explored the potential of glucagon-like peptide-1 receptor agonists(GLP-1RAs)as a novel intervention to modify the disease course and delay the onset of T1D.GLP-1RAs are medications initially developed for treating type 2 diabetes.They exert their effects by enhancing glucose-dependent insulin secretion,suppressing glucagon secretion,and slowing gastric emptying.Emerging evidence suggests that GLP-1RAs may also benefit the treatment of newly diagnosed patients with T1D.This article aims to highlight the potential of GLP-1RAs as an intervention to delay the onset of T1D,possibly through their potential immunomodulatory and anti-inflammatory effects and preservation of beta-cells.This article aims to explore the potential of shifting the paradigm of T1D management from reactive insulin replacement to proactive disease modification,which should open new avenues for preventing and treating T1D,improving the quality of life and long-term outcomes for individuals at risk of T1D. 展开更多
关键词 Type 1 diabetes Semaglutide Glucagon-like peptide-1 receptor agonists Insulin therapy Autoimmune response Blood glucose monitoring Β-cell preservation Early screening Teplizumab Randomized controlled trials
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Y-1中间砧苹果地上部不同器官与组织矿质营养分配
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作者 李汇斌 康积玮 +3 位作者 王艳芳 王骞 杨廷桢 郝燕燕 《北方园艺》 CAS 北大核心 2024年第1期31-37,共7页
以Y-1中间砧的‘烟富3号’为试材,对树体地上部枝条和果实不同器官与组织矿质元素进行测定,研究了不同器官与组织矿质营养的分配特性,以期为苹果周年生产科学施肥提供参考依据。结果表明:N、P、Mg在种子中分配占比最高,果实中占比最少;... 以Y-1中间砧的‘烟富3号’为试材,对树体地上部枝条和果实不同器官与组织矿质元素进行测定,研究了不同器官与组织矿质营养的分配特性,以期为苹果周年生产科学施肥提供参考依据。结果表明:N、P、Mg在种子中分配占比最高,果实中占比最少;K元素含量在各器官与组织中分配差异较小,相对其他元素其在果实中积累最高;Ca元素在叶片中分配占比最高。种子中N、P、K、Mg在花后90 d时积累达到最高后处于较高水平且变化平缓;果皮中Mg元素含量分配显著高于果心和果肉;P、K、Mg元素在韧皮部中含量变化较为活跃,在花后90 d韧皮部中P、K、Mg分配均显著升高。综上可知,Y-1中间砧矮化苹果施肥管理应注重秋后基肥或花后追施N、P、Mg,果实膨大期补施K肥,在花后及果实膨大期补充Ca肥。 展开更多
关键词 Y-1中间砧 矮化苹果 矿质元素 营养分配
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波塞冬1组患者重复周期应用早卵泡期长效长方案和拮抗剂方案的疗效比较及自身对照研究 被引量:1
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作者 明子琳 李婉晴 +1 位作者 唐志霞 洪名云 《生殖医学杂志》 CAS 2024年第1期8-16,共9页
目的探讨早卵泡期长效长方案和拮抗剂方案在波塞冬1组患者重复周期中的应用疗效及优化策略。方法选择2018年6月至2022年6月于安徽省妇幼保健院生殖中心行体外受精(IVF)/卵胞浆内单精子注射(ICSI)治疗、采用常规控制性促排卵(COH)方案发... 目的探讨早卵泡期长效长方案和拮抗剂方案在波塞冬1组患者重复周期中的应用疗效及优化策略。方法选择2018年6月至2022年6月于安徽省妇幼保健院生殖中心行体外受精(IVF)/卵胞浆内单精子注射(ICSI)治疗、采用常规控制性促排卵(COH)方案发生非预期卵巢低反应(uPOR)、且助孕失败后再次助孕的波塞冬1组患者286例为研究对象,根据重复周期COH方案不同分为早卵泡期长效长方案组(简称早长方案组,n=119例)和拮抗剂方案组(n=167例),比较两组实验室指标及临床妊娠结局;并将其中前后两个周期均采用相同COH方案的124例患者分为双早长方案组(n=70例)和双拮抗剂方案组(n=54例),采用自身对照研究分析两组临床资料。结果(1)再次COH周期早长方案组与拮抗剂方案组患者间基础资料比较无统计学差异(P>0.05)。早长方案组促性腺激素(Gn)总量、Gn天数、HCG日E_(2)水平、获卵数、可用胚胎数及优质胚胎数均显著高于拮抗剂方案组(P<0.05),HCG日LH水平显著低于拮抗剂方案组(P<0.05),其鲜胚种植率、鲜胚临床妊娠率及累积妊娠率较拮抗剂方案组有升高趋势,但无统计学差异(P>0.05);两组患者间周期取消率、中重度卵巢过度刺激综合征(OHSS)发生率、HCG日孕酮(P)水平、HCG日内膜厚度、再次uPOR发生率及早期流产率等比较均无统计学差异(P>0.05)。(2)双早长方案组的自身对照比较结果显示,再次早长方案组Gn启动剂量、LH添加量、HCG日E_(2)水平、获卵数、可用胚胎数、优质胚胎数、正常受精率、优质胚胎率、鲜胚种植率和临床妊娠率均显著高于首次早长方案组(P<0.05),早期流产率显著低于首次早长方案组(P<0.05)。(3)双拮抗剂方案组的自身对照比较结果显示,再次拮抗剂方案组Gn启动剂量、LH添加量、获卵数、可用胚胎数、优质胚胎数、鲜胚种植率及临床妊娠率等均显著高于首次拮抗剂方案组(P<0.05)。结论对于波塞冬1组患者来说,早卵泡期长效长方案和拮抗剂方案均可作为重复周期的促排卵方案;从获卵数及鲜胚临床妊娠结局考虑,早卵泡期长效长方案优于拮抗剂方案;从经济成本考虑,拮抗剂方案优于早卵泡期长效长方案。重复周期可根据两个方案的劣势采取优化措施来改善患者对于促排卵方案的反应性及卵母细胞质量和数量等问题,从而改善IVF/ICSI预后。 展开更多
关键词 非预期卵巢低反应 波塞冬1 早卵泡期长效长方案 拮抗剂方案 自身对照研究
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基于L_(1/2)范数的非局部PCA泊松噪声图像恢复改进算法
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作者 李欢 张文娟 +1 位作者 黄姝娟 肖锋 《咸阳师范学院学报》 2024年第2期10-15,30,共7页
为增强NLSPCA(非局部稀疏主成分分析)算法对去除图像泊松噪声性能,提高图像块聚类精确度,增大字典下的表示系数稀疏性,改善恢复图像易模糊等问题,提出基于L_(1/2)范数的非局部PCA泊松噪声图像恢复改进算法(L_(1/2)-NLSPCA)。新算法首先... 为增强NLSPCA(非局部稀疏主成分分析)算法对去除图像泊松噪声性能,提高图像块聚类精确度,增大字典下的表示系数稀疏性,改善恢复图像易模糊等问题,提出基于L_(1/2)范数的非局部PCA泊松噪声图像恢复改进算法(L_(1/2)-NLSPCA)。新算法首先对图像分割成重叠块;其次采用设计的自适应Bregman K-means算法对分割的图像块聚类;最后使用PCA构建基于L_(1/2)范数的非局部字典下的稀疏表示系数,对聚类后的图像块分组进行去噪重构。实验结果表明,L_(1/2)-NLSPCA算法与基准算法相比峰值信噪比(PSNR)提高了0.52~2.57 dB,在视觉上纹理细节更清晰。 展开更多
关键词 泊松分布 图像去噪 主成分分析 L_(1/2)范数
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前癃通胶囊介导miR-216a-5p/TPT1/mTORC1通路调控良性前列腺增生的实验研究
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作者 黄鸿宇 郭子莘 +7 位作者 朱文雄 袁轶峰 贺菊乔 刘涛 谭梅鑫 杨金玉 曹雨昙 张熙 《湖南中医药大学学报》 CAS 2024年第3期374-382,共9页
目的通过细胞实验探讨前癃通胶囊(qian long tong capsule,QLTC)能否通过调控miR-216a-5p/肿瘤蛋白翻译控制1/哺乳动物雷帕霉素靶蛋白复合物1(miR-216a-5p/tumor protein translationally controlled 1/mammalian target of rapamycin c... 目的通过细胞实验探讨前癃通胶囊(qian long tong capsule,QLTC)能否通过调控miR-216a-5p/肿瘤蛋白翻译控制1/哺乳动物雷帕霉素靶蛋白复合物1(miR-216a-5p/tumor protein translationally controlled 1/mammalian target of rapamycin complex 1,miR-216a-5p/TPT1/mTORC1)信号通路抑制良性前列腺增生(benign prostatic hyperplasia,BPH)。方法将25只大鼠随机分为对照组(等体积生理盐水),QLTC低(56.25 mg/mL)、中(112.50 mg/mL)、高(225.00 mg/mL)剂量组,LBSC组(168.75 mg/mL),每组5只。每组灌胃1 mL/次,2次/d,连续5 d。各组大鼠麻醉后制备含药血清。根据实验目的不同,将CP-H022细胞分5步做实验处理,每部分实验进行独立分组。将miR-216a-5p过表达和沉默表达,及TPT1过表达进行对照研究;RT-qPCR法检测正常和BPH模型CP-H022细胞内miR-216a-5p表达量,并观察不同浓度QLTC处理的BPH细胞中miR-216a-5p表达量的差异;细胞集落形成实验检测细胞增殖能力;CCK-8法检测BPH模型细胞增殖;RT-qPCR法检测miR-216a-5p、TPT1 mRNA表达水平;流式细胞术检测细胞凋亡;生信分析、双荧光素酶实验验证miR-216a-5p与TPT1的靶向关系;过表达TPT1后,Western blot法检测BPH细胞中TPT1/mTORC1信号通路相关分子表达情况。结果与对照组1比较,模型组1的CP-H022细胞内miR-216a-5p表达量下调(P<0.05);不同浓度的QLTC均能上调miR-216a-5p表达量(P<0.05);根据本实验结果,本研究将选用QLTC(高剂量)组CP-H022细胞进行后续实验。与模型组2比较,QLTC组2细胞增殖减少、凋亡增加(P<0.05),B细胞淋巴瘤-2(B-cell lymphoma-2,Bcl-2)表达降低(P<0.05),Bcl-2关联X蛋白单克隆抗体(monoclonal antibody to Bcl-2 associated X protein,Bax)、cleaved Caspase-3表达升高(P<0.05)。敲低miR-216a-5p后,与模型组4比较,QLTC组4细胞增殖增强、凋亡减少(P<0.05),Bcl-2表达升高(P<0.05),Bax、cleaved Caspase-3表达降低(P<0.05)。与mimic-NC组比较,miR-216a-5p mimic组TPT1表达量降低(P<0.05);QLTC处理后,细胞TPT1、p-mTORC1表达均降低(P<0.05);过表达TPT1后BPH细胞增殖功能增强(P<0.05),凋亡减少(P<0.05),Bcl-2表达升高(P<0.05),Bax、cleaved Caspase-3表达下降(P<0.05)。结论QLTC可通过介导miR-216a-5p下调TPT1/mTORC1通路,进而抑制BPH。 展开更多
关键词 前癃通胶囊 良性前列腺增生 细胞实验 miR-216a-5p 肿瘤蛋白翻译控制1 哺乳动物雷帕霉素靶蛋白复合物1 信号通路
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胰高血糖素样肽1受体激动剂治疗合并超重或肥胖的2型糖尿病的疗效和安全性的Meta分析 被引量:2
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作者 俞恬 刘少华 +4 位作者 魏安华 郭洁茹 张程亮 刘东 刘喆隆 《药物流行病学杂志》 CAS 2024年第5期519-538,共20页
目的系统评价胰高血糖素样肽1受体激动剂(GLP-1RA)治疗合并超重或肥胖2型糖尿病(T2DM)患者的有效性与安全性。方法计算机检索PubMed、Embase、Cochrane Library、Ovid、ClinicalTrial.gov、SinoMed、CNKI、WanFang Data和VIP数据库,搜... 目的系统评价胰高血糖素样肽1受体激动剂(GLP-1RA)治疗合并超重或肥胖2型糖尿病(T2DM)患者的有效性与安全性。方法计算机检索PubMed、Embase、Cochrane Library、Ovid、ClinicalTrial.gov、SinoMed、CNKI、WanFang Data和VIP数据库,搜集有关GLP-1RA治疗T2DM合并超重或肥胖患者的随机对照试验(RCT),检索时限均从2005年1月1日至2023年11月1日。由2位研究者独立筛选文献、提取资料并评价纳入研究的偏倚风险后,采用R软件进行Meta分析,并采用GRADE系统进行证据质量评价。结果共纳入71个RCT,包括29476例患者。Meta分析结果显示,相比于其他降糖药,GLP-1RA在改善糖化血红蛋白[WMD=-0.55,95%CI(-0.65,-0.45),P<0.001]、减重[WMD=-2.61,95%CI(-3.25,-1.97),P<0.001]方面均具有优势;GLP-1RA对空腹血糖的改善效果呈时间依赖性[16周以内:WMD=0.25,95%CI(-0.17,0.66),P=0.250;16~52周:WMD=-0.06,95%CI(-0.32,0.20),P=0.650;>52~104周:WMD=-1.67,95%CI(-1.91,-1.43),P<0.001];安全性方面,GLP-1RA的总体不良反应发生率较高[RR=1.11,95%CI(1.07,1.15),P<0.001];但低血糖发生率低于胰岛素[RR=0.58,95%CI(0.48,0.71),P<0.001],而与口服降糖药的差异无统计学意义[RR=0.83,95%CI(0.58,1.19),P=0.310]。GRADE系统评价显示,仅低血糖发生率的证据等级为中等,其余结局指标的证据水平均为低级。结论当前证据显示,对于T2DM合并肥胖或超重患者,GLP-1RA尤其是司美格鲁肽相比于安慰剂、胰岛素或口服降糖药,能更有效兼顾降糖和减重,虽总体不良反应较多,但可减少低血糖发生。 展开更多
关键词 胰高血糖素样肽1受体激动剂 2型糖尿病 肥胖或超重 疗效 安全性 META分析 随机对照试验
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ApoA-1水平与老年急性心肌梗死患者心梗后院内心衰的相关性
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作者 梁霄 刘韧 +3 位作者 张杰 罗亚 秦玲 徐敏 《微循环学杂志》 2024年第1期31-35,共5页
目的:探讨老年急性心肌梗死患者住院期间血清载脂蛋白A-1(ApoA-1)水平与早发心梗后心衰的关系。方法:回顾性收集我院2020-01—2021-04诊断为急性心肌梗死的老年患者207例,根据患者是否发生心衰将其分为心衰组(n=93)和非心衰组(n=114),... 目的:探讨老年急性心肌梗死患者住院期间血清载脂蛋白A-1(ApoA-1)水平与早发心梗后心衰的关系。方法:回顾性收集我院2020-01—2021-04诊断为急性心肌梗死的老年患者207例,根据患者是否发生心衰将其分为心衰组(n=93)和非心衰组(n=114),比较两组患者临床基线资料(年龄、性别、既往病史等)及生化指标(血脂、肾功能)的差异。采用Logistic回归分析ApoA-1与老年急性心梗后心衰的相关性。运用ROC曲线评价ApoA-1和其它相关指标对老年患者早发心梗后心衰的预测效能。结果:与非心衰组患者比较,心衰组患者总胆固醇、高密度脂蛋白胆固醇以及ApoA-1水平均降低(P<0.05);多因素Logistic回归分析结果显示ApoA-1和NT-proBNP与老年患者早发心梗后心衰的发生独立相关(P<0.05);ROC曲线分析结果表明ApoA-1和NT-proBNP预测老年患者早发心梗后心衰事件的AUC分别为0.624(95%CI:0.547-0.702,P<0.01)和0.749(95%CI:0.680-0.819,P<0.01),当二者联合应用后其预测效能提升(AUC=0.780, 95%CI:0.714-0.846,P<0.01)。结论:ApoA-1和NT-proBNP可用于预测老年急性心梗后住院期间心衰事件的发生,并且与心衰事件独立相关。 展开更多
关键词 载脂蛋白A-1 急性心肌梗死 心力衰竭 病例对照研究
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